package basic;

/**
 * @author Cheng Jun
 * Description: System 类的学习
 * 先看类注释：
 * The System class contains several useful class fields and methods. It cannot be instantiated.
 * System类包含一些 静态方法和静态变量（类方法，类变量），它不能被实例化。
 * Among the facilities provided by the System class are standard input, standard output, and error output streams;
 * System类提供的工具包括标准输入流、标准输出流和错误输出流;
 * access to externally defined properties and environment variables;
 * 访问外部定义的属性和环境变量;
 * a means of loading files and libraries;
 * 一种加载文件和库的方法;
 * and a utility method for quickly copying a portion of an array.
 * 以及用于快速复制数组的一部分的实用方法。  
 * @version 1.0
 * @date 2021/12/28 9:38
 * @see System
 * @see System.props
 */
public class SystemStudy {

    /**
     * System.props
     * @author Cheng Jun
     * @date 2021/12/28 13:34
     * @param args
     * @return void
     * @see System.props
     */
    public static void main(String[] args) {
        System.out.println(System.getProperty("user.dir") + System.getProperty("file.separator"));
        System.out.println(System.getProperty("user.home") );
        System.out.println(System.getProperty("java.class.path") );
        System.out.println(SystemStudy.class.getResource("") );
    }

}
